Pneumatic sound-regulating mechanism for mechanical pianos and the like.



L. J. VILAR.

PNEUMATIC SOUND REGULATING MECHANISM FOR MECHANICAL PIANOS AND THE LIKE.

APPLICATION FILED JUNE 1, 1914.

1,204,831. Patented Nov. 14, 1916.

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LUIS JOVELL VILAB, OF BARCELONA, SPAIN.

mun'nc SOUND-BEGULATING mncmtmsn r03. nncnnmcnr. PIANOS AND m Specification of Letters Patent.

Patented Nov. 14, 1916.

Application filed June 1, 1814. Serial No. 842,167.

To all whom it may concern Be it known that I, LUIs JOVELL VILAR, a subject of the King of Spain, residing at Barcelona, in Spain, have invented certain new and useful Improvements in Pneumatic Sound-Regulating Mechanism for Mechanical Pianos and the like, of which the followingris a specification.

he present invention relates to improvements in pneumatic regulating mechanism intended to be applied to mechanical pianos or the like.

The improvements are for the purpose of increasing the striking power for chords and consequently increasing the sound produced,

providing two degrees of soft pedal action, and providing improved means for emphasizing certain notes from the rest of the harmony.

The improved mechanism can be applied to all kinds of pneumatically operated pianos or the like.

The annexed drawings illustrate the mechanism in question in which Figure 1 is a vertical section. Fig. 2 is a transverse section on line AA of Fig. 1. Fig. 3 is a section in plan of the operat ing mechanism for producing the various effects. Figs. 4 and 5 are respective sections on lines CC and DD of Fig. 3. Fig. 6 is a transverse section of the music sheet rollers showing the arrangement of the tracker-board and of a tube through which the air for the automatic note emphasis passes.

The apparatus comprises a box 45 in direct communication through pipe 26 with the main suction bellows of the player mechanism. The box 45 comprises two chambers 22 and 23 respectively in direct and constant communication by means of the conduits 32 and 31 with the motor pneumatics of the player mechanism on the right side and on the left side of the piano. These chambers can be put in communication by the openings 43, 44 and 27, 28 with the interior of the box. The openings 43 and 44 are open or shut according to the operation of the throttle valves 46 and 47. The openings 27 and 28 are never totally closed and the degree of opening thereof is regulatable.

The apparatus shown in Fig. 1 is symmetrical on each side of the plane passing through the axis of the tube 26, each half corresponding to one of the halves of the piano, the arrangement and function being conse uently equal it is only necessary to descri e one half; I will describe that on the left hand side in the drawings. The top 2 of the box is formed of a wooden plate covered with sheeting on both faces; the top 2 1s provided with a hole to which the tube 6 is applied (Figs. 1, 3, 4 and 5) which is thus in communication with a chamber 8 housing a valve 10- somewhat smaller than the chamber. This latter has an orifice 12 through which passes the rod 14 which connects the valve to a foot 16 which rests on an extensible membrane 18 closing the well 20. The well 20 is in communication by the channel with the vacuum chamber 45 and by the tube 67 with the tracker-board. The chamber 22 constantly communicates as previously mentioned with the vacuum chamber 45 through theopening 28 and regulating valve 30, which is connected by the rod 36 to the head of a bellows 34 which is in communication with the chamber 22 by means of the tube 38; the movement of the bellows 34 takes place against the action of a spring plate 40 which constitutes a regulator for the power of the air current passing through 28. The stroke of the bellows 34 can be regulated by a nut 42 serving as an abutment for the plate 40. The opening 44 of the chamber 22 can be closed by the throttle valve 46 constituted by the top of bellows having rectilinear movement, the bottom of which is fixed to the bottom 5 of the box. The chamber 48 of these bellows communicates with the chamber 8 by means of a channel 52 (Fig. 2) and with the box 45 by the passage 50. Inside the chamber 22 are small bellows 54 which can be put in communication with the atmosphere through tube 58 (Figs. 1 and 5) and by the capillary tube 56 with the chamber 22. The head of the bellows 54 is opposite the regulating valve 30 and transfers its movements to the latter.

The mechanism shown in Figs. 3. 4 and 5 is naturally arranged in duplicate, that is for each half of the piano; it comprises a manually controlled valve consisting of a plate spring 63 carrying a button intended to be depressed by the finger of the person playing the piano, in order to uncover the mouth 61 of tube 6; if the button is still further depressed, the spring 63 is put in contact with a plate spring 64 and the latter uncovers the mouth 62 of the tube 58.

I will now describe the action of the mechanism: To produce a great volume of sound, it is suflicient to keep the mouth 61 of tube 6 closed; then by means of the capillary conduit'50 the pressure of the air in 48, 52, 8 and 6 will be equal to that in 45 and the throttle valve 46 will be in its lowest position-due to gravity and the pressure exercised on its upper surface by the air which comes from the bellows of the notes and is passing'to the vacuum chamber 45. Theopening 44 is 'fully open, the suction willbe effectual to its fullest extent and the sounds, without any reduction, will correspond to the energy developed by the main bellows. To produce the soft pedal action or constant reduced sound it is sufiicient to push the button 65 to overcome the action of the spring .63 and thus uncover the mouth of the tube 6; then the air will flow through 6 to chamber 8 and the conduit 52 and will pass into the chamber 48, wherein it will expand due to the rarefaction of the air in 45,

so that the valve 46 will rise and close the conveniently regulated by adjusting the po- 7 sition of the nut 42 as previously explained to obtain the desired amount of reduction of sound. To produce a still greater constant reduction of sound, it is suflicient to depress the button 65 farther until it overcomes the action of spring 64, which opens the mouth 62; the air will then flow through 58 to the bellows 54 where it will expand and cause the displacement of the head of said bellows toward the valve 30 and which will push the valve against the opening 28, the passage of which will thus be reduced, producing the further reduction of sound sought for In order to explain that this further sound reduction is always constant independently of the number of key pneumatics discharging their air into the chamber 22, as well as of the suction prevailing, it is sufficient to observe that an increase of rarefaction, in the air in 22 produces a proportional increase in the interior expansion of the bellows 54, which is translated by an increase of" thrust to the valve 30 and consequently by a proportional diminution of the size of opening 28.

The automatic note emphasis is obtained as follows: It is necessary to effect the reduction of sound of the general harmony; for this purpose the button is depressed so as to open either the mouth 61 only, or both the mouths 61 and 62. In this position each time-hole of the music strip uncovers the mouth of the tube 67, atmospheric air will flow through same. Consequently the membrane 18 will be pushed up and the .valve 10 lifted, stopping the communication between the tube 6 and the chamber 48 while between said chamber 48 and the Vacuum chamber 45 a new communication will be established through the orifice 12 left air from notes through 44 and consequently again obtained.

What I claim as my invention and desire to secure by Letters Patent of the United States is 1. In pneumatic sound regulating mechanism for mechanicalpianos and the like the combination of a throttle valve, pneumatic means for actuating said valve, said actuating means including an air conduit, a manually controlled valve for closing said air conduit, a second valve adapted to close said air conduit while said manually controlled valve is open,-pneumatic means for actuating said second .valve, and a tracker board having a passage connected to said last mentioned pneumatic means.

2. In pneumatic sound regulating mechanism for mechanical pianos and the like the combination of a suction conduit, a chamber having two wall apertures for communication with said conduit and an orifice for connection to motor pneumatics, a throttle valve controlling one of said wall apertures, pneumatic means for actuating said valve, said actuating means including an air conduit, a

controlling the second wall aperture, and a pneumatic control device for'said regulating valve comprising a bellows, an air conduit connected to said bellows and manually controlled means for opening and closing the last mentioned air conduit.

In witness whereof I have signed this specification in the presence of two witnesses.

LUIS J OVELL VILAR. Witnesses:

NARCISO JUBEsE,

JUAN PANAUA. 

